This project is focused on the clinical problem of strabismus. The macaque monkey will be used as an experimental model to examine the underlying mechanisms of strabismus. In children with strabismus, the image from the deviated eye is suppressed. The mechanism whereby this suppression occurs is unknown. This proposal probes the psychophysical, physiological and anatomical basis of visual suppression in awake behaving monkeys raised with strabismus. After measurement of fixation preference and acuity in strabismic monkeys, areas of suppression in the visual field will be mapped under binocular conditions. Electrophysiological recordings will then be performed to determine how single cell activity in regions ofcortex corresponding to suppression scotomas is modulated by changes in ocular fixation. Subsequent anatomical experiments will correlate local levels of metabolic activity, reflected by cytochrome oxidase histochemistry in ocular dominance columns, with suppression scotomas. Taken together, it is hoped that this approach, the first using a conscious macaque model in strabismus, will shed light on this important clinical problem. [unreadable] [unreadable]